THE 



POPULAR SCIENCE 



MONTHLY. 



JULY, 1908 



SOIL WASTAGE 



By Peofessor THOMAS CHROWDER CHAMBERLIN, Ph.D., LL.D., Sc.D. 



UNIVERSITY OF CHICAGO 



THE invitation to give thought to the conservation of resources 

 that affect our future, appeals to me with almost personal force, 

 for my studies of the past decade have led to the belief that the era 

 of the earth's future habitability is vastly greater than we have been 

 wont to think. We have grown up in the belief that the earth sprang 

 from chaos at the opening of our era and is plunging on to catastrophe 

 or to a final winter in the near future. Quite at variance with this, 

 I have come to believe that the earth arose from a regenerative process 

 and that it offers a fair prospect of fitness for habitation for tens of 

 millions of years to come. If this be true, it is eminently fit that our 

 race should give a due measure of thought to the ulterior effects of its 

 actions. 



It is one of the latest conceptions of geology that climatic condi- 

 tions have been of the same order as at present from early eras, in 

 the large view, in spite of some notable variations, and that this uni- 

 formity is the result of a profound regulative system which has sufficed 

 to keep the temperatures of the earth's surface and the constitution of 

 the earth's atmosphere within the narrow range congenial to life for 

 many millions of years. As a result there has been no break in the 

 continuity of land life since it came into being eras ago. It appears, 

 further, that the sources of supply of the vital elements are still ade- 

 quate, and are likely to be so for long ages, that the regulative system 

 is still in effective control, and that a vast future of habitability may 

 fairly be predicted, subject only to some contingencies of collision or 

 disturbing approach of celestial bodies. Whether you are prepared to 

 accept so large a view of the habitable future or not, I trust you will 



